The following essay is part of a series in which dozens of women will reveal what women they most admire. The series is part of “Women Rule,” a unique effort this fall by POLITICO, Google and The Tory Burch Foundation exploring how women are leading change in politics, policy and their communities. See more essays here.

When I started thinking about running for the Senate, there was just one person — after my husband — I knew I had to consult: Barbara Mikulski.

At the time, the tough-as-nails former social worker from Maryland was one of only two women serving in the Senate, and the first Democratic woman elected in her own right.

She sat me down and got right to the point. “How old are you, Babs?” she asked. I said, almost 50.

She told me it was the perfect time, and that if I was ready to give up my safe House seat for a long-shot Senate bid: “You can do more here, you can be heard here, and it’s worth the fight you’ll have to wage to get here. And it will be a fight.”

Was she ever right. After a tough campaign, I was elected in 1992, the Year of the Woman, when we tripled the number of female senators — from two to six.

Sen. Mikulski has never been satisfied just making history herself — she wanted to blaze a trail wide enough for all of us to follow. As she said: “Some women stare out the window waiting for Prince Charming. I stare out the window waiting for more women senators!”

Twenty years later, there are now 20 women in the Senate — and we all have stories about Sen. Mikulski reaching out to us, encouraging us, mentoring us and helping us along the way.

Just days after I won that first Senate race, she sent all the new Senate women a guidebook she wrote, “Getting Started in the Senate,” and invited us to her office for lessons on Senate procedure, committee assignments and setting up our offices.

Since then, she has hosted regular dinners for all Senate women at which we come together across party lines to talk about our work and families, and share our struggles and our triumphs. And she has led by example, showing colleagues how to build coalitions and bridge the partisan divide, while always staying true to her values.

In the Senate, there are some who have passion, some with sharp policy skills, some who are brilliant negotiators, some who are great students of history and some who are champions for the least among us. Sen. Mikulski is all these things.

As her colleagues know, she is also flat-out hilarious. When asked at one point how she felt about being named Glamour’s Woman of the Year along with singer Madonna, Sen. Mikulski replied, “She’s got her assets, I have mine, and we both make the best of what God has given us.”

She is famous for what I fondly call her “Mikulski-isms.” During legislative battles, she challenges the Senate women to go “earring to earring” with our opponents and to “put on our lipstick, square our shoulders, suit up and fight!”

At 4 feet 11 — just about my height — she may not look like a fighter. But no one fights harder for the middle class, for women, for families, for seniors, for veterans, for all of us.

She has never forgotten her roots, growing up in a blue-collar neighborhood in East Baltimore, the daughter of a grocer. In many ways, she is still that community leader who helped save Baltimore’s Inner Harbor by stopping a 16-lane highway from slashing through Fell’s Point.

Every day in the Senate, she shows her relentless determination to make life better for the people she serves, whether it’s ensuring equal pay for equal work, fighting for a better education for our kids, providing mammograms and other lifesaving care for women, promoting medical research to help all our families or working to restore her beloved Chesapeake Bay.

And she is still making history. In 2011, she became the longest-serving woman in Senate history. In 2012, she became the longest-serving woman in Congress. And earlier this year, she became the first woman to take the gavel of the powerful Senate Appropriations Committee.

From the day she was first sworn in, Barbara Mikulski has carried the challenges, the hopes and the dreams of millions of women with her. She has inspired generations of young women everywhere.

The Senate used to be a very lonely place for women, but Sen. Mikulski changed that. That’s why she will always be known as the Dean of the Senate women — our cherished leader — because she opened up the doors of the Senate wide enough to let the women of America walk in.